“We have a lot of extra capacity coming,” promises Dave Saska, AT&T’s vice president of engineering.

AT&T, Verizon and Sprint plan to deploy “Cell on Wheels,” mobile trucks for extra network coverage, in key locations that are expected to get heavily hit, most notably rural Madras, Oregon, which is both home to the huge SolarFest and the state where the total eclipse will first be seen, around 10:15 a.m. PT.

The carriers are also focusing on Hopkinsville, Kentucky, where the path of totality will last the longest, at 2 minutes and 40 seconds. (Or, as it says on the town webpage, “the point of greatest eclipse.”)

The more folks surrounding you, whether it be a rural or urban location (like Nashville, St. Louis or Charleston, where the eclipse ends), the less likely it will be that you’ll get on the network.

—Disable app updates temporarily. This saves your cellular data bandwidth and lets you use it for stuff you really care about on August 21, like possibly sending out selfies.

—Fully charge up before you leave, and bring along an extra power pack. This won’t get you extra coverage, but it will keep you connected on a long day if your battery runs out. We’re big fans of the Mophie packs, which start at $60 for battery powered smartphone cases that will give you a full additional charge.

—Try a mobile hotspot device, or a second phone, maybe. Wireless carriers sell mobile hot spot devices for around $50 plus additional monthly service. One could potentially help, but probably not. In our experience at major events, our Verizon Mifi didn’t make it any easier to get connected. A second phone on another carrier might do the trick. Perhaps AT&T has better coverage in your area than Verizon, or there are fewer AT&T customers than T-Mobile there.

—Record the video, for later. Don’t live stream. “If you’re in that position where everyone is competing for bandwidth, record the video instead of live streaming, and post it later,” says Saska. But a livestream to a site like Facebook or Twitter takes ten to 20 megabits per minute, vs. a photo, which is 3 megabits.

In other words, livestreaming takes more bandwidth than anything else you might do on eclipse day.

Saska won’t predict that August 21st will be the busiest day of the year for AT&T. The eclipse is on a Monday, which happens to be a low-peak day for traffic, and it’s not during drive-time commute time, when more people are on than other times, he says.

Still, AT&T is prepared for 2.5 times the amount of normal coverage. “It’s unprecedented,” he says, a sentiment echoed by Verizon, Sprint and T-Mobile.

This will be the first coast-to-coast U.S. eclipse since 1918, a time that pre-dates modern communication. We still had party lines back then.

Adds Verizon spokesperson Karen Schulz: “This is a once in a lifetime occurrence that spans across the entire nation and is not a normal network day.”

Should you really, really want to live stream, and have access to an ethernet connection and a router, we have a seriously wonky solution for you.

You can get your iPhone into a router via cabling, but it will take several pieces to make it happen.

Adding ethernet to the iPhone isn't hard.(Photo: Jefferson Graham)

With a nod to Jacob Salmela, who has written about this on his blog, you’ll need: A USB to ethernet adapter, Apple’s USB 3 Camera adapter (MK0W2AM/A), a powered USB hub, a USB to USB cable, and a Lightning to USB cable.

Go to settings on your device, turn off Wifi, and voila, the ethernet shows up right under Bluetooth. You’re connected.

(We tried this over the weekend, and once you had all the right parts and cables, which took two trips to Best Buy, it all worked flawlessly.)

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